Vague Question of the day

[akeem_da_dream]

Hello again guys!

Driving today, blasting my music, and there's a gradual HUMMMMMMMMMMM sound coming from the car. at first it was the sub-woofer, so I paused the music, and it continued until i slowed down. It happened two more times today while running errands, each occurring around 50-55 mph.

Definitely not from the engine, feels like it's coming from the wheels, like something is rubbing, but when i got out of my car, no tires are rubbing anything. Nothing is hanging down or looks different from the ordinary.

If it helps to know the front bearings have been replaced months ago, the suspension is stock, and an alignment was done last year

The car doesn't shake as if the wheels were out of balance, but the HUMMMMMMMMMMM is clearly audible, and the rear view mirror shakes.

Oh yea, 85 ptype, 216k, 5 spd

[1982 Dragon]

Wheel Bearing.

[akeem_da_dream]

thanks, if that's the case, how long do i have before they go whammy kablammy? broke until next week.

[1982 Dragon]

Um. Not right away but they may start leaking. That could mess up your brakes.
So I would try to get them done.
They are a pain in the butt... hopefully not too expensive and hopefully you can still buy them!

[Rich64N]

Could be a sticking brake caliper. After stopping, put the back side of your hand to each of the rims and feel for heat on one (not the palm, more heat sensing nerves on the back if you don't know that already), Easy test at least.

[pdupler]

For the car to vibrate, the wheel bearing would have to be really really bad and he would have heard them making metal-to-metal noise long before I'd think. Just thinking of things that can also make the car vibrate like that - mabe a u-joint or that the rubber section of that center bearing on the driveshaft, or the transmission mount has broken? Or mabe you did lose a wheel weight. We're all just guessing tho.

[StanS]

wheel bearing is hi pitch and usually not confined to 50-55mph. my guess is rear wheel balance.

[akeem_da_dream]

Could be a sticking brake caliper. After stopping, put the back side of your hand to each of the rims and feel for heat on one (not the palm, more heat sensing nerves on the back if you don't know that already), Easy test at least.

funny you should mention that, the last time i changed my pads they were not equally worn.

even funnier is that the sound never came back the day i reported this loud hum. over the past few months i would get a quieter hum, but no vibration at all.

food for thought: i had to buy a used tire since one of my tires blew. its a 235 instead of 225 like my other three wheels are.

[tyrantfour]

differential whine

is it sensitive to throttle?

[akeem_da_dream]

no its not, its really random. not sure if it would be the diff since i changed the oil on it already